Gardeners use multiple methods for growing new plants, including starting them from seeds, bulbs, and rhizomes. However, when the goal is to produce a plant identical to an existing plant, taking a cutting is usually the simplest way. A cutting is a 4- to 8-inch section of stem taken from a healthy plant and then put in water or a growing medium to root. Propagating by cutting is suitable for many types of plants, including some species of trees and bushes, but it’s especially well suited to the indoor gardening plants that tend to grow well from cuttings. Even those who aren’t familiar with advanced gardening concepts and are just trying to clone a favorite plant from a planter can often be successful with cuttings.
Cuttings from some plants, such as ivy and Dieffenbachia, root easily in plain water. Others need a little encouragement, and that’s where rooting hormone comes in. Rooting hormones are chemicals that stimulate the growth of new roots on cuttings. For example, the odds of growing a plant from a cutting taken from a cascading plant in a hanging planter increase when a rooting hormone is used. Finding the best rooting hormone is somewhat a matter of personal preference because most rooting hormone products are very similar. Ahead, learn what to look for in a rooting hormone product and find out why the following five are among the top choices of home gardeners.
- BEST OVERALL: Clonex HydroDynamics Rooting Gel
- RUNNER UP: Hormex Rooting Hormone Powder #3
- BEST CONCENTRATE: Hormex Vitamin B1 Rooting Hormone Concentrate
- ALSO CONSIDER: Bonide 925 Bontone Rooting Powder
- ALSO CONSIDER: Hormex Rooting Hormone Powder #8
What to Consider When Choosing the Best Rooting Hormone
Rooting hormone products are relatively inexpensive and range from around $13 for a bottle that will treat up to 50 cuttings to $25 (or more) for a large container that will treat more than 100 cuttings. The most significant difference is in the type of product and whether it contains added ingredients, such as nutrients or fertilizers intended to help the plant grow and thrive once the cutting develops roots.
Rooting hormone products come in three main types: liquid, gel, and powder. No matter the type, all three are used in a similar manner: the gardener dips the end of the cutting in the hormone product and then puts the cutting in a moist, growing medium.
- Liquid: Bottles of liquid rooting hormone come in either ready-to-use formulations or concentrated formulations that require mixing with water. Some gardeners feel liquid offers the best coverage since it can seep into tiny pores in the cutting.
- Gel: This rooting hormone adheres well to cuttings and provides a slightly thicker coating of the hormone than liquid varieties, which may offer more root-boosting stimulus.
- Powder: One of the most common types of root hormone products available, powder is simple to use and offers a thick layer of root-stimulating chemical. Before dipping the cutting in the powder, many gardeners will dip the cutting in water, so the root hormone adheres better.
The majority of rooting hormone products on the market today contain one of two common chemicals, IBA or NAA, both of which are synthetic forms of natural plant hormones known to stimulate root growth.
- Indole-3-butyric acid (IBA): A chemical form of the plant hormone, auxin, IBA triggers root growth and is found in many commercial rooting hormone products of all types.
- Naphthaleneacetic acid (NAA): Similar to IBA, NAA is a synthetic chemical formulation that stimulates root growth and retards rotting. It is often found in all three types of rooting products.
- Added nutrients: While IBA and NAA are the active ingredients in rooting compounds, some products contain additional nutrients, such as nitrogen, to boost leafy green growth or have various vitamins to help bolster floral production. These added ingredients can be helpful, but some gardeners prefer to use only rooting compound, so they can add the exact nutrients they choose to the soil later.
The information necessary for propagating cuttings is available in gardening books, but, for the most part, the process is straightforward and simple enough for even newbie gardeners. The following offers an idea of the basic techniques used for taking cuttings and applying rooting hormone. Before proceeding, do a little research on the intended plant. While cuttings can successfully propagate many plants, others require different methods. Some cuttings should be from greenwood (new, supple growth), while others should be taken from the older, hardwood portions of a stem. Knowing the best method of propagation for a specific plant will increase the odds of success.
- Take a 4- to 8-inch stem cutting from a healthy plant.
- Strip all but one or two top leaves from the stem.
- Bruise the end of the stem by slightly crushing it or take a sharp knife and scrape away some of the stem’s outer covering. This step helps the rooting hormone penetrate more efficiently.
- Dip about 2 inches of the stem in the rooting compound. If you’re using a powdered mixture, dip the cutting in water first, so the powder adheres well.
- With a pencil or stick, make a hole about 2 inches deep in the growing medium and insert the treated end of the cutting.
- Press the growing medium around the cutting and cover the whole pot or tray with plastic to keep moisture in while the cutting takes root. By keeping the cutting in an enclosed container, the soil will stay moist, which is a requirement for roots to develop. Alternately, consider starting the cutting in a self-watering planter where it will receive a consistent amount of moisture.
Our Top Picks
To qualify as a Top Pick, a rooting hormone should be simple to apply, the instructions should be easy to understand, and the product should contain either IBA or NAA to promote root growth. The following five products feature different types of rooting hormone—including liquid, powder, and gel—but all are top performers popular with experienced gardeners. Any one of the products in the lineup will be an asset for propagating plants from cuttings.
Looking for the sticking power of an easy-to-use gel? Consider this option from Clonex that contains the active ingredient IBA for stimulating root growth. The gel seals the cut tissue around the stem, helping to protect it from rot while encouraging strong root development. The gel is suitable for use on different types of cuttings, including flowering species, woody plants, and fruit tree cuttings, among others. The jar contains 3.4 fluid ounces, plenty for rooting dozens of cuttings. There’s no mixing or mess, just dip the stem in the gel and insert it into a moist growing medium.
- Gel formula seals cut tissue around stem
- Suitable for starting variety of cuttings
- Contains IBA to stimulate root growth
- Requires no mixing or mess
- More expensive than some rooting hormones
To propagate new cuttings, consider this rooting powder from Hormex that helps prevent stem rot while stimulating new root development. The powder, which can also help strengthen and bolster sagging cuttings, is suitable for use on most plants that can be propagated from cuttings. The active ingredient is IDA. The Hormex powder does not contain added chemicals, dyes, or preservatives, making it desirable for use on vegetables and fruit plants used in food production. In addition to treating cuttings, it is also beneficial for helping transplants adapt to a new location. Hormex #3 comes in a ¾-ounce jar.
- Powder form that can bolster sagging cuttings
- IBA as active ingredient
- Contains no added chemicals, dyes, or preservatives
- Also can boost root growth in transplants
- Small quantity of powder
- Adheres better by dipping cutting in water first
Also from Hormex, this rooting hormone features the active ingredient NAA and comes in a concentrated liquid form that will treat dozens of cuttings. To use, dip a fresh cutting into the undiluted rooting hormone and insert the cutting in a moist growing medium. For an added root-boosting effect, mix 1 teaspoon of Hormex concentrate in 1 gallon of water and use the solution to saturate the soil around the new cutting. When transplanting newly rooted plants, use the same liquid solution for watering to reduce transplant shock. The inclusion of Vitamin B in the Hormex product adds a vital nutrient to the soil for robust plant growth. Best of all, the rooting hormone is available at an attractive price point.
- Affordable concentrated liquid
- Active ingredient of NAA
- Includes vitamin B1 to add nutrients
- Can dilute for use on transplants
- Strong concentrate might require mixing with water
- NAA is a synthetic chemical
Bonide’s rooting powder is well suited for helping establish healthy, robust roots on stem cuttings, but it’s also useful for encouraging strong growth when planting seeds and bulbs. The active ingredient, IBA, stimulates root growth on most cuttings, including softwoods, hardwoods, vegetables, and flowering varieties. It comes in powder form and can also be used to coat seeds and bulbs by sprinkling it directly on them before planting. When transplanting a plant to a new location, users can also mix a teaspoon, or so, of the powder in the growing medium to reduce transplant shock and help the plant adapt. Each jar contains 1.25 ounces, enough for a few dozen cuttings or transplants.
- Versatile rooting hormone for many cutting types
- Also boosts growth of seeds and bulbs
- Can ease transplant shock
- Active ingredient of IBA
- Powder works best if cutting dipped in water first
- Package of four might be more than needed
For quick rooting of most cuttings, opt for a rooting hormone like this one that contains the active chemical IBA. Suitable for use in most plants, including greenwood and softwood cuttings, this Hormex option is formulated to promote the development of healthy roots. The product comes in powder form for easy application. A singe jar contains 2 ounces of powder—plenty for rooting many dozens of cuttings. For best results, take cuttings only from the current season’s growth from a healthy mother plant. Dip the end of the cutting in water before dipping it in the powdered rooting hormone.
- Quick-adding formula with IBA
- Suitable for cuttings from most plants
- Package contains 2 ounces of powder
- Free of dyes and preservatives
- Requires dipping cutting in water before powder
The best rooting hormone can protect and boost growth of cuttings to propagate new plants. Our top pick, Clonex HydroDynamics Rooting Gel, seals cut tissue and boosts root development. Those who prefer a powder might prefer Hormex Rooting Hormone Powder #3, which can strengthen and protect sagging cuttings while boosting root growth.
How We Chose the Best Rooting Hormones
Use of a rooting hormone can help gardeners duplicate favorite plants from cuttings. Although most rooting products are similar, we looked at types and some features of products to help buyers choose based on personal preference. This list includes liquid, gel, and powder formulas and a choice of the two most common active ingredients. We also considered application methods and ease of use.
The application of rooting hormone increases the odds of success when propagating with cuttings. The product stimulates root growth and reduces the risk of stem rot. For gardeners new to the product, a few questions are to be expected.
Q. How does a rooting hormone work?
A rooting hormone stimulates root growth at the cut end of a stem.
Q. Is rooting hormone necessary for cuttings?
Not always, but it’s handy to have around. Some plants, especially indoor plants, can root in just plain water.
Q. How long will my rooting hormone take to work?
Depending on the plant, roots should start to develop within two to six weeks. Research the plant you’re trying to propagate for a specific timeline.
Q. Do rooting hormone solutions work for hydroponic plants?
Rooting hormones are often used in hydroponic systems to stimulate plant growth.